Tyre sizes

[Keith479]

I have 20 inch rims fitted from new on a 2010 model , what size tyres should I have fitted. Im sure the dealer has fitted the wrong size and this is why I can't get replacements.

[Pilgrim]

Originally Posted by Keith479

I have 20 inch rims fitted from new on a 2010 model , what size tyres should I have fitted. Im sure the dealer has fitted the wrong size and this is why I can't get replacements.

Check your owner's manual and it will tell you the correct tire sizes. If you are saying that the 20" tires came on the vehicle, then you just need to run the size stated in the manual.

You don't say whether these are stock wheels or whether you have increased the wheel diameter.

If you have changed from 18" to 20" tires, just go online and find websites such as Discounttire.com and Tirerack.com which provide plus-sizing information. As you increase the diameter of the wheels, you decrease the sidewall ratio. The purpose is to keep the same total diameter of the wheel/tire combination to keep the speedometer and odometer accurate.

Just do a search for "tire plus sizing guide".

[BillArf]

I run 255/50/R20 tires on my 2011 Murano LE . This is -not- what the Murano running 20's leaves the factory with but a valid replacement.


235/55/R20 tire is what comes on the 20" rim leaving the factory.

[Keith479]

Pilgrim.
Thanks for the info, the was supplied into the UK with 18s and a dock side grade was completed before it was delivered to the dealer.

[Keith479]

Checked the recommended tyre size on the tyre plus guide and they should be 255 50 r20
Thanks for the info guys. Going off to the dealer in the morning to confront them.

[BillArf]

Originally Posted by Keith479

Checked the recommended tyre size on the tyre plus guide and they should be 255 50 r20
Thanks for the info guys. Going off to the dealer in the morning to confront them.

Did you read my post? While 255/50/R20 is a very good choice for the 20" Murano rim, again, not the size tire it leaves the factory with. Leaves factory with 235/55/R20 tire.

[Pilgrim]

Two notes about the slight differences:

1) If you run the same tire size on ALL FOUR corners, then there will be no damage to the powertrain caused by different sized tires.

2) Running tires which do not match the original diameter of the factory tires will result in some speedometer and odometer error. As I think Bill implies above, some brands with slightly different sidewall profiles are so close in diameter to OEM that the difference is moot.

As a side note, it is typical for car speedometers read a couple of MPH slow, so if you have tires just *slightly* larger than OEM diameter, they may be pretty darn accurate on the speedo.